The arguments comparing both, DTD and BPD, has been back and forth for a couple of decades without finding a common ground. Developmental Trauma Disorder (DTD) was proposed to be included in the DSM and it was rejected because it’s too similar to Borderline Personality Disorder (BPD). Still, the DSM doesn’t consider BPD a trauma-related disorder, and therefore, its treatment focuses on behavior and “flaws” in personality, instead of targeting the regulation of the nervous system. This is the reason the conversation should keep going.
If the psychiatric community has not accepted formal and well structured/researched propositions for developmental trauma (or complex trauma for that matter), we are still far from having other manifestations of the trauma phenomena even considered. One of those manifestations, or subdivisions, is Attachment Trauma.
The same way that there are differences between C-PTSD and Developmental Trauma because it’s clearly different to suffer traumatization in a developed brain than in a developing brain, it is different also to suffer traumatization in childhood due to neglect or abuse than to suffer traumatization in childhood due to emotional abandonment, lack of attunement, and/or emotional disconnection. Those are subtle and sometimes difficult to see them as causes of trauma, but for a newly born, are life-threatening.
From what I have learned and observed, BPD is more connected to Attachment trauma than to Developmental trauma. At the same time, I have observed that ALL personality disorders are connected to Developmental trauma; which means, that if someone suffers from attachment trauma and from developmental trauma as well, the chances to develop a personality disorder increases exponentially.
How does borderline personality disorder emerge from developmental trauma?
A personality disorder, in general, can emerge from developmental trauma (DTD) because the prolonged exposure to danger, terror, confusion, threat, etc., not only alters memories or mood regulation, but also distorts the perception of reality and of the self.
BPD, in particular, can emerge from DTD because rejection, criticism, and emotional abandonment stops the development of the self, creates shame, and leaves the kid in a never-stop need to be comforted.
BPD is the personality disorder that is more connected to neediness, and to the lack of capacity to find comfort. That comes from having grown up in an environment where comfort was not available, and where the caregiver didn’t satisfy the needs of the baby. Not having basic needs met as a baby is terrifying, and trauma develops from fear and the feeling of hopelessness. I'm not talking here about emotional needs. I'm talking about basic needs like the need to stop the discomfort of being dirty, or wet, or cold, or hungry. At the very beginning of life we are more concerned to survive than to be loved. Babies are all about their primitive brain learning to regulate the most basic functions like digestion, sleep cycle, temperature, etc. That's why babies at the beginning have no schedule to eat or sleep. Their nervous system is just adapting to be outside the womb. The homeostasis (the tendency toward a relatively stable equilibrium between interdependent elements, especially as maintained by physiological processes) is just starting to find balance.
A baby that is not attended feels rejected and not worthy of attention and develops shame for being unlovable, for feeling like a burden, for the perception of being defective. Remember that kids internalize the negative feedback from caregivers because it’s easier to survive in a good world as a bad kid, than surviving in a bad world as a good kid. Better believe the problem is him/herself, instead of living afraid of the parents. That’s why so many BPD defend the mother so strongly, idealizing her to the extreme of perfection, as a way to convince the incipient mind that there is hope.
That confusion evolves as a disorganized attachment, and as splitting. One trait at a time, the adult presents with a set of deficiencies, distortions, misconceptions, and personality manifestations that meet criteria for a personality disorder.
Why isn't CPTSD just borderline personality disorder if they're both caused by developmental trauma?
First of all, remember that C-PTSD and Developmental Trauma Disorder (DTD) are not officially recognized as diagnoses. There are proposals for both, and apparently the WHO (World Health Organization) is going to include C-PTSD in the next version of their manual, the ICD-11 (International Classification of Diseases 11th version) but not yet.
Second, many scholars have been trying to have BPD seen as related or developed from trauma, but the APA (American Psychiatric Association) keeps denying that fact and keeps arguing that BPD is genetically based.
Even if the diagnosis for the 3 were all accepted and standardized, there is a difference between the 3 of them.
C-PTSD is more similar to PTSD in terms of symptoms with the difference that PTSD is normally connected to a single event, while C-PTSD is connected to a series of events, or to prolonged exposure to a traumatic situation. That can happen at any age, and therefore, should not be considered equivalent to developmental trauma. They are not the same, and the consequences are very different. Saying that C-PTSD is the same as DTD is a disservice to the community.
Separating them gives space to prevent traumatization in childhood, or to better understand children’s behavior and the internal distress that has been ignored for too long.
Developmental trauma is the recognition that traumatization early in life has consequences on the development of the brain and nervous system. This is huge in terms of treatment planning and case conceptualization since many of the byproducts of developmental trauma are treated as illness on their own, and medicated without the context of the dysregulation of the nervous system and the root of the problem. Examples are ADD and ADHD, depression, reactive attachment disorder, anxiety, learning disorder, dyslexia, etc.
BPD is a manifestation in the personality and behavior caused possibly by Attachment Trauma, perhaps combined with developmental trauma. Some people with BPD don’t even report developmental trauma and much less attachment trauma; attachment trauma is subtle and it may not look like abuse or neglect. It’s a type of emotional neglect that can be silent, and invisible.
Responding to the WHY in the question, it's fair to say that the more we understand the differences between the several causes or disarrays in the brain, mind, and sense of self of the individuals that suffer from any of the disorders, the better they will be served in terms of clinical interventions. If we see them all as the same, their treatment will be less effective.
Each individual is very special and unique, and putting them in broad boxes (one size fits all) doesn’t serve them well. It doesn’t serve the therapist either.
The more clarity about all the possible detonators of changes and alterations in thinking, behaving, and feeling, the more specific the treatment could be to help to resolve the emotional conflicts.
Diagnosis could be considered roadmaps; the more roads, the better chances to reach your destination. Their use is not restricted to get paid by insurance companies. They are useful to guide the client and the therapist in recognizing and addressing the issues that need to be treated. If we consider them all the same, we lose all the local roads to achieve our goal of reaching mental health.
(Originally appeared in Quora as three different questions)